An air mass is a large body of air with uniform temperature and humidity. The area from which an air mass originates is called a source region. Air masses are classified according to the temperature and moisture content of their source regions.
Air mass classification based on temperature fall under one of three categories
- Arctic (A) – Extremely cold air mass
- Polar (P) – A cool to cold air mass
- Tropical (T) – A warm to hot air mass
Air mass classification based on moisture fall under one of two categories
- Continental (c) – A dry air mass that develops over land
- Maritime (m) – A moist air mass that develops over water
Example: A very cold and dry air mass is known as a Continental Arctic (cA) airmass
